diff --git a/lib/Analysis/LoopDependenceAnalysis.cpp b/lib/Analysis/LoopDependenceAnalysis.cpp index b23459e81ac..4912bf27591 100644 --- a/lib/Analysis/LoopDependenceAnalysis.cpp +++ b/lib/Analysis/LoopDependenceAnalysis.cpp @@ -40,6 +40,16 @@ static inline bool isMemRefInstr(const Value *I) { return isa(I) || isa(I); } +static void getMemRefInstrs( + const Loop *L, SmallVectorImpl &memrefs) { + for (Loop::block_iterator b = L->block_begin(), be = L->block_end(); + b != be; ++b) + for (BasicBlock::iterator i = (*b)->begin(), ie = (*b)->end(); + i != ie; ++i) + if (isMemRefInstr(i)) + memrefs.push_back(i); +} + //===----------------------------------------------------------------------===// // Dependence Testing //===----------------------------------------------------------------------===// @@ -71,16 +81,30 @@ void LoopDependenceAnalysis::getAnalysisUsage(AnalysisUsage &AU) const { } static void PrintLoopInfo( - raw_ostream &OS, const LoopDependenceAnalysis *LDA, const Loop *L) { + raw_ostream &OS, LoopDependenceAnalysis *LDA, const Loop *L) { if (!L->empty()) return; // ignore non-innermost loops OS << "Loop at depth " << L->getLoopDepth() << ", header block: "; WriteAsOperand(OS, L->getHeader(), false); OS << "\n"; + + SmallVector memrefs; + getMemRefInstrs(L, memrefs); + OS << " Load/store instructions: " << memrefs.size() << "\n"; + OS << " Pairwise dependence results:\n"; + for (SmallVector::const_iterator x = memrefs.begin(), + end = memrefs.end(); x != end; ++x) + for (SmallVector::const_iterator y = x + 1; + y != end; ++y) + if (LDA->isDependencePair(*x, *y)) + OS << "\t" << (x - memrefs.begin()) << "," << (y - memrefs.begin()) + << ": " << (LDA->depends(*x, *y) ? "dependent" : "independent") + << "\n"; } void LoopDependenceAnalysis::print(raw_ostream &OS, const Module*) const { - PrintLoopInfo(OS, this, this->L); + // TODO: doc why const_cast is safe + PrintLoopInfo(OS, const_cast(this), this->L); } void LoopDependenceAnalysis::print(std::ostream &OS, const Module *M) const { diff --git a/test/Analysis/LoopDependenceAnalysis/dg.exp b/test/Analysis/LoopDependenceAnalysis/dg.exp new file mode 100644 index 00000000000..f2005891a59 --- /dev/null +++ b/test/Analysis/LoopDependenceAnalysis/dg.exp @@ -0,0 +1,3 @@ +load_lib llvm.exp + +RunLLVMTests [lsort [glob -nocomplain $srcdir/$subdir/*.{ll,c,cpp}]] diff --git a/test/Analysis/LoopDependenceAnalysis/siv-strong1.ll b/test/Analysis/LoopDependenceAnalysis/siv-strong1.ll new file mode 100644 index 00000000000..01f11137d78 --- /dev/null +++ b/test/Analysis/LoopDependenceAnalysis/siv-strong1.ll @@ -0,0 +1,30 @@ +; RUN: llvm-as < %s | opt -disable-output -analyze -lda > %t +; RUN: grep {instructions: 3} %t | count 1 +; RUN: grep {0,2: dependent} %t | count 1 +; RUN: grep {1,2: dependent} %t | count 1 + +; for (i = 0; i < 256; i++) +; x[i] = x[i] + y[i] + +@x = common global [256 x i32] zeroinitializer, align 4 +@y = common global [256 x i32] zeroinitializer, align 4 + +define void @foo(...) nounwind { +entry: + br label %for.body + +for.body: + %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ] + %y.addr = getelementptr [256 x i32]* @y, i64 0, i64 %i + %x.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i + %x = load i32* %x.addr + %y = load i32* %y.addr + %r = add i32 %y, %x + store i32 %r, i32* %x.addr + %i.next = add i64 %i, 1 + %exitcond = icmp eq i64 %i.next, 256 + br i1 %exitcond, label %for.end, label %for.body + +for.end: + ret void +} diff --git a/test/Analysis/LoopDependenceAnalysis/siv-strong2.ll b/test/Analysis/LoopDependenceAnalysis/siv-strong2.ll new file mode 100644 index 00000000000..e64b92c3e76 --- /dev/null +++ b/test/Analysis/LoopDependenceAnalysis/siv-strong2.ll @@ -0,0 +1,31 @@ +; RUN: llvm-as < %s | opt -disable-output -analyze -lda > %t +; RUN: grep {instructions: 3} %t | count 1 +; RUN: grep {0,2: dependent} %t | count 1 +; RUN: grep {1,2: dependent} %t | count 1 + +; for (i = 0; i < 256; i++) +; x[i+1] = x[i] + y[i] + +@x = common global [256 x i32] zeroinitializer, align 4 +@y = common global [256 x i32] zeroinitializer, align 4 + +define void @foo(...) nounwind { +entry: + br label %for.body + +for.body: + %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ] + %y.ld.addr = getelementptr [256 x i32]* @y, i64 0, i64 %i + %x.ld.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i + %i.next = add i64 %i, 1 + %x.st.addr = getelementptr [256 x i32]* @x, i64 0, i64 %i.next + %x = load i32* %x.ld.addr + %y = load i32* %y.ld.addr + %r = add i32 %y, %x + store i32 %r, i32* %x.st.addr + %exitcond = icmp eq i64 %i.next, 256 + br i1 %exitcond, label %for.end, label %for.body + +for.end: + ret void +} diff --git a/test/Analysis/LoopDependenceAnalysis/ziv1.ll b/test/Analysis/LoopDependenceAnalysis/ziv1.ll new file mode 100644 index 00000000000..e42c0a08cb2 --- /dev/null +++ b/test/Analysis/LoopDependenceAnalysis/ziv1.ll @@ -0,0 +1,23 @@ +; RUN: llvm-as < %s | opt -disable-output -analyze -lda > %t +; RUN: grep {instructions: 2} %t | count 1 +; RUN: grep {0,1: dependent} %t | count 1 + +; x[5] = x[6] + +@x = common global [256 x i32] zeroinitializer, align 4 + +define void @foo(...) nounwind { +entry: + br label %for.body + +for.body: + %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ] + %x = load i32* getelementptr ([256 x i32]* @x, i32 0, i64 6) + store i32 %x, i32* getelementptr ([256 x i32]* @x, i32 0, i64 5) + %i.next = add i64 %i, 1 + %exitcond = icmp eq i64 %i.next, 256 + br i1 %exitcond, label %for.end, label %for.body + +for.end: + ret void +} diff --git a/test/Analysis/LoopDependenceAnalysis/ziv2.ll b/test/Analysis/LoopDependenceAnalysis/ziv2.ll new file mode 100644 index 00000000000..cecf3a750b6 --- /dev/null +++ b/test/Analysis/LoopDependenceAnalysis/ziv2.ll @@ -0,0 +1,26 @@ +; RUN: llvm-as < %s | opt -disable-output -analyze -lda > %t +; RUN: grep {instructions: 2} %t | count 1 +; RUN: grep {0,1: dependent} %t | count 1 + +; x[c] = x[c+1] // with c being a loop-invariant constant + +@x = common global [256 x i32] zeroinitializer, align 4 + +define void @foo(i64 %c0) nounwind { +entry: + %c1 = add i64 %c0, 1 + %x.ld.addr = getelementptr [256 x i32]* @x, i64 0, i64 %c0 + %x.st.addr = getelementptr [256 x i32]* @x, i64 0, i64 %c1 + br label %for.body + +for.body: + %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ] + %x = load i32* %x.ld.addr + store i32 %x, i32* %x.st.addr + %i.next = add i64 %i, 1 + %exitcond = icmp eq i64 %i.next, 256 + br i1 %exitcond, label %for.end, label %for.body + +for.end: + ret void +}